1. Field of the Invention
This invention relates to the use of selected pyridine-N-oxide disulfide compounds to prevent or treat bovine mastitis.
2. Description of the Prior Art
Bovine mastitis is an infection of the udder of ruminants such as cows, mainly caused by gram positive bacteria and especially in cows in intensive milk producing units. It results in the inflammation of the mammary gland (i.e., teats and udder). The disease is particularly troublesome and of considerable economic importance because the pathogen is readily transferred from one animal to another during the milking process. Some of the main pathogens causing bovine mastitis are Staphylococcus aureus, Streptococcus agalactiae, Streptococcus uberis, Streptococcus dysgalactiae, Escherichia coli, Aerobacter aerogenes, Klebsiella pneumoniae, and Pseudomonas aeruginosa.
Effective compounds to be used in the treatment or prevention of bovine mastitis should give the following results:
1. Most or all of the above pathogens should be susceptible to the compound when the latter is in milk and other udder fluids.
2. The therapeutic effect should be relatively quick.
3. No significant irritation should be caused to the teats or udder of the cow, either by the active compound or other ingredients used with it.
4. The active compound should not stay in the milk for a period much in excess of the one required for the therapeutic activity so as to minimize the loss of milk, which has to be discarded when as an undesired foreign compound is present.
There are other requirements for such a composition for the treatment of bovine mastitis but the above four criteria are some of the most important ones.
Bovine mastitis has so far been treated mainly by administering anti-microbial agents such as antibiotics, e.g. Penicillin G, Dihydrostreptomycin, and the like. However, it has been recently found to be very desirable to replace antibiotics by non-antibiotic drugs. The following are some reasons why:
1. Antibiotics effective in human medicine should not be utilized in veterinary medicine, in order not to build up a strain resistance against bacteria appearing in human diseases.
2. Staphylococcus aureus, one of the above-noted pathogens, has already built up a resistance against most of the antibiotics utilized in the treatment of bovine mastitis.
It thus is very important to find a method for the treatment of bovine mastitis utilizing a nonantibiotic compound which substantially would overcome the desired results as set out above. U.S. Pat. No. 4,401,666, which issued to J. H. Wedig et al on Aug. 30, 1983, claims a method for treating animals for bovine mastitis with at least one metallic salt of pyridine 2-thione-N-oxide. This patent is incorporated herein by reference in its entirety.